The present invention is essentially an improvement of the customer terminal shown in U.S. Pat. No. 3,841,584 to Robinson et al. An incoming carrier in that terminal passes first through a valve in the receive tube and then into the rear of an inner compartment having an inclined floor down which the carrier rolls into a tray just behind and carried by a bottom hinged door on the front of the terminal normally closing the compartment. In the latter position, the carrier straddles the mouth of the send tube which opens up through the tray. When a customer's car arrives before the terminal, a tape switch opens the door to present the carrier to the customer who dispatches it to the teller by dropping it down the send tube, whereupon the door closes. Upon its return, the carrier again rolls into the tray, opening the door so that the customer can pick up the carrier. When finished, the customer returns the carrier to the tray and drives off over the tape switch which then closes the door.
One aspect of the system just described is that, unlike other pneumatic systems for drive-up banking purposes and the like, the inner compartment into which the carrier arrives forms no part of the pneumatic circulatory system per se. Rather, the air can circulate and a carrier travel through the send and receive tubes quite independently of whether the compartment is open or closed. In other pneumatic drive-up banking systems, however, the inner compartment or its equivalent is an integral part of the circulatory system in the sense that the system cannot function if the compartment is open nor, indeed, unless it is largely air tight. Several advantages accrue from the system of the Robinson et al patent.
By divorcing the inner compartment from the pneumatic circulatory system, operation of the blower need not be tied to whether the compartment is open or closed. Hence, the blower can run continously, regardless of whether the compartment is open, in the event that humidity or temperature conditions would be apt to cause condensation in the underground tubes were the blower run only when a carrier is sent. Or the blower can be set to operate only when a carrier is actually being transported through the tubes. Construction of the compartment is thereby greatly simplified since it and the outer access door need not be air tight. Nor is the opening and closing time of that door at all critical; it can be opened or closed at any time regardless of the location of the carrier in the tubes since the pneumatic system operates irrespective of whether the door is open or closed.
The improvement of the Robinson et al system, which forms the present invention, will now be briefly recounted.